EMIR is a second generation GTC instrument. EMIR's external structure is a huge cylindrical vacuum chamber of 2.2m length and 1.8m in diameter with a weight of around 5 tons, with the instrument inside on a floating optical bench at the LN2 temperature in a cryogenicaly poumped system. The instrument is mounted on the optical bench over a double cold base. The verification of the optical system and its alignment on the optical bench, as well as the alignment of the optical axis with respect to the vacuum chamber and the whole set to the rotator, are the critical tasks that will validate the feasibility and functionality of this instrument.